Bayer gets US green light for colorectal cancer drug Stivarga

Follows FDA approval for Sanofi and Regeneron's Zaltrap in same indication

The US Food and Drug Administration (FDA) has approved Bayer's new colorectal cancer drug Stivarga following a review period of just five months on the back of data showing it can improve survival.

Stivarga (regorafenib) - a multi-kinase inhibitor that blocks several enzymes that promote cancer growth - has been given a green light as a second-line treatment for patients with metastatic colorectal cancer, just weeks after the FDA cleared Sanofi and Regeneron's Zaltrap (ziv-aflibercept) for the same indication.

Bayer's drug improved overall survival in these patients by an impressive 29 per cent in the phase III CORRECT trial, leading some observers to suggest that the drug could become a new standard of care. It also had a significant impact on progression-free survival (PFS) and disease control rates.

"The approval of regorafenib adds to the treatments we have for metastatic colorectal cancer, which is important for those patients who have no further options," said CORRECT investigator Heinz-Josef Lenz of the USC Norris Comprehensive Cancer Center.

"The drug has been shown to prolong survival and slow the progression of cancer in patients whose disease had progressed after treatment with currently available therapies. It provides patients another avenue to fight this cancer," he added.

CORRECT showed that even in a hard-to-treat population which had been exposed to earlier chemotherapy regimens, regorafenib was able to boost overall survival to 6.4 months versus 4.0 months with placebo.

Similarly, PFS was increased to 2.0 months from 1.7 months with placebo, while the disease control rate was nearly 45 per cent in those treated with Bayer's drug and just 15 per cent for the control group.

Regorafenib is one of four late-stage compounds that Bayer has predicted could collectively add €5bn to its revenues at peak. The company filed regorafenib as a treatment for gastrointestinal stromal tumours (GIST) in the US in August and the drug has also been filed for colorectal cancer in Europe.

The compound caused a dispute between Bayer and partner Onyx Pharmaceuticals, which filed a lawsuit in 2009 claiming rights to the drug under the terms of an alliance between the two firms which led to the development of kidney and liver cancer drug Nexavar (sorafenib).

The suit was settled last year after the two companies agreed that regorafenib is a Bayer compound but Onyx would receive a 20 per cent royalty on sales.